The Expression And Clinical Significance Of ERCC1,RRM1 And TUBB3 In Non-small-cell Lung Cancer

Background: Lung cancer is one of the most common malignant tumors in the world. For the high morbidity and mortality of lung cancer, it is becoming a hot spot of modern medical research. Non-small cell lung cancer( NSCLC) is a most devastating cancer with insidious early symptom, rapid progression and poor prognosis in advanced stage, and about 80%-85% of lung cancer is NSCLC. So, the adjuvant chemotherapy is one of the most important treatments for NSCLC. But, the efficacy of chemotherapy is variable and unpredictable in NSCLC, even if with same regimen and dose.Previous studies suggest that the heterogeneity of tumor cell is the reason for the divergent chemotherapeutic sensitivity and effectiveness.The expression of chemotherapy sensitivity associated is an important maker to Assess chemotherapeutical sensitivity and effect.Therefore, the chemosensitivity assay and chemosensitivity associated genes analyses are important for making therapy plan. Chemotherapy sensitivity associated genes in lung cancer have been widely investigated in recent years, such as ERCCl, RRM1, TUBB3 and TYMS. Many researches were demonstrated that the level of m RNA was consisted with the expression of protein in these genes. However, some studies had shown that the m RNA of ERCC1 was not always in line with the expression of protein in tumors. So, the relationship of m RNA and protein expression need to further study. In this study, we performed two methods real-time fluorescent polymerase chain reaction(RT-PCR) and immunohistochemistry(IHC) to detecting the level of m RNA and protein of ERCC1, RRM1 and TUBB3 in patients with NSCLC.Objective: This study detecting the level of m RNA and protein in ERCC1, RRM1 and TUBB3, and analysis the relationship between m RNA expression and protein expression in three genes.We investigated proteinexpression and the clinicopathological features in patients with NSCLC,and provide the basis for clinical rational use of chemotherapy drugs.Methods: The study was performed retrospectively on patients who underwent resection between January 2010 and September 2012 at Hebei Chest Hospital. All patients were confirmed by pathology after surgery for non-small cell lung cancer, and the clinicopathological features of these patients were also analyzed. The level of m RNA and protein in ERCC1, RRM1 and TUBB3 were detected by RT-PCR and IHC. The control group is the adjacent tissues of tumors from 40 patients. The statistical comparisons were performed usingχ2 test and fisher’s exact test. All statistical analyses were performed using the SPSS software program, version 17.0.Results:1 The level of m RNA of ERCC1, RRM1 and TUBB3 in NSCLC.RT-PCR showed that the m RNA of ERCC is positive in 34(34%) cases and negative or low expression in 66(66%) cases; positive in 52(52%) cases and negative or low expression in 48(48%) cases for RRM1; positive in 33(33%) cases and negative or low expression in 67(67%) cases for TUBB3.2 The expression of ERCC 1, RRM1 and TUBB3 in NSCLC.IHC showed that ERCC 1, RRM1 and TUBB3 highly expressed in 43, 38 and 31 of 100 cases. In control group, ERCC 1, RRM1 and TUBB3 highly expressed in 4, 3 and 2 of 40 cases, respectively. ERCCl, RRM1`and TUBB3 in NSCLC was higher than that in adjacent tissues. Chi-square test results show that the difference was statistically significant(P<0.05).3 The protein expression and m RNA expression of ERCCl, RRMl, TUBB3 with consistency.The consistent rate between m RNA and protein is 77%, 70% and 76% in ERCCl, RRMl and TUBB3. The m RNA level well correlated with the protein expression in ERCCl, RRMl and TUBB3.(r=0.528,P=0.000;r=0.422,P=0.000;r=0.449,P=0.000).4 The correlation between ERCCl, RRM1 and TUBB3 and clinicopathological features of NSCLC.The expressions of ERCCl, RRM1 and TUBB3 have no relationship with gender, age,histological subtype,tumor differentiation,TNM staging(P>0.05).5 Correlation analysis between the protein expression of ERCCl and RRMl.For protein, ERCC1 and RRM1 highly expressed in 27 cases simultaneously; highly ERCC1 expressed with low RRM1 expressed in 16 cases; highly RRM1 expressed with low ERCC1 expressed in 11 cases; ERCC1 and RRM1 low expressed in 46 cases simultaneously. The expression of ERCC1 and RRM1 were positively correlated(r=0.357,P=0.001) by pairing χ2 test and spearman’s rank correlation coefficient analysis.6 Correlation analysis between the protein expression of ERCCl and TUBB3.For protein, ERCC1 and TUBB3 highly expressed in 27 cases simultaneously; highly ERCC1 expressed with low TUBB3 expressed in 16 cases; highly TUBB3 expressed with low ERCC1 expressed in 4 cases; ERCC1 and TUBB3 low expressed in 53 cases simultaneously. The expression of ERCC1 and TUBB3 were positively correlated(r=0.597, P=0.000) by pairing χ2 test and spearman’s rank correlation coefficient analysis.Conclusions:1 The expression of ERCC1, RRM1 and TUBB3 in NSCLS significantly higher than that in adjacent tissues. It suggested these genes may be associated with tumorigenesis and progress.2 The level of protein and m RNA are well collected in ERCC1, RRMl and TUBB3 in NSCLC.3 The expressions of ERCCl, RRM1 and TUBB3 had no correlation with gender, age, histological subtype, tumor differentiation, TNM staging(P> 0.05).4 The expression of ERCC1 was positively correlated with RRM1 in NSCLC.5 The expression of ERCC1 was positively correlated with TUBB3 in NSCLC.